title: 3'-[(1H-Indol-3-yl)carbon-yl]-1'-methyl-2-oxo-4'-(thio-phen-2-yl)-spiro-[indoline-3,2'-pyrrolidine]-3'-carbo-nitrile.
abstract: In the title compound, C26H20N4O2S, the central pyrrolidine ring adopts a twist conformation on the C-C bond involving the spiro C atom. Its mean plane makes dihedral angles of 78.83 (14), 65.91 (15) and 44.49 (18)° with the mean planes of the adjacent oxindole ring system, the indole system and the thio-phene ring, respectively. The indole and indoline units are essentially planar, with maximum deviations of 0.019 (3) and 0.090 (3) Å, respectively. In the oxindole fused-ring system, the pyrrole ring adopts an envelope conformation with the spiro C atom as the flap. In the crystal, pairs of N-H⋯O hydrogen bonds link the mol-ecules, forming inversion dimers with an R (2) 2(8) ring motif. The dimers are linked by further N-H⋯O hydrogen bonds, forming a two-dimensional network lying parallel to (100).
authors.affiliation: Sri Ram Engineering College, Chennai 602 024, India.
authors.forename: S Antony
authors.initials: SA
authors.lastname: Inglebert
authors.forename: Yuvaraj
authors.initials: Y
authors.lastname: Arun
authors.forename: K
authors.initials: K
authors.lastname: Sethusankar
authors.forename: Paramasivam T
authors.initials: PT
authors.lastname: Perumal